There is a known way of using a pulse width modulated signal for the proportional control of an on-off valve. A valve of this kind is typically returned to a default position, for example a closed position, and can be actuated to another position, for example an open position, by means of a control signal.
It is desirable to have a precise knowledge of the flow rate through a valve of this kind.
There is a known way of estimating a flow rate through an on-off valve actuated by a pulse width modulated control signal, by calculating a flow rate value for each control cycle. There is also a known document US 2003/0005916 A1 which proposes to calculate a flow rate value once in every two control cycles. However, this temporal resolution appears to be insufficient for certain applications, such as the control of a fuel vapor filter purge valve.